Submission #626727

#	Time	Username	Problem	Language	Result	Execution time	Memory
626727		CSQ31	Road Construction (JOI21_road_construction)	C++17	100 / 100	2309 ms	245560 KiB

road_construction

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define all(a) a.begin(),a.end()
#define pb push_back
#define owo ios_base::sync_with_stdio(0);cin.tie(0);
#define fi first
#define se second 
#define sz(a) (int)(a.size())
typedef pair<int,int> pii;
vector<ll>glo;
const int MAXN = 1e8,INF = 2e9+1;
pii t[MAXN];
int ch[2][MAXN];
int ndcnt = 0;
int nwnode(int v = -1){
	ndcnt++;
	int u = ndcnt;
	t[u] = {-INF,0};
	if(v!=-1){
		t[u] = t[v];
		ch[0][u] = ch[0][v];
		ch[1][u] = ch[1][v];
	}
	return u;
}
void pull(int v){
	t[v] = {-INF,0};
	if(ch[0][v])t[v] = max(t[v],t[ch[0][v]]);
	if(ch[1][v])t[v] = max(t[v],t[ch[1][v]]);
}
int build(int l,int r){
	if(l==r){
		int u = nwnode();
		t[u].se = l;
		return u;
	}
	int u = nwnode();
	int tm = (l+r)/2;
	ch[0][u] = build(l,tm);
	ch[1][u] = build(tm+1,r);
	pull(u);
	return u;
}
int upd(int v,int l,int r,int pos,int val){
	if(l==r){
		int u = nwnode();
		t[u] = {val,pos};
		//cout<<l<<" "<<r<<" "<<t[u].fi<<" "<<t[u].se<<'\n';
		return u;
	}
	int u = nwnode(v);
	int tm = (l+r)/2;
	if(pos <= tm)ch[0][u] = upd(ch[0][v],l,tm,pos,val);
	else ch[1][u] = upd(ch[1][v],tm+1,r,pos,val);
	pull(u);
	//cout<<l<<" "<<r<<" "<<t[u].fi<<" "<<t[u].se<<'\n';
	return u;
}
pii query(int v,int l,int r,int tl,int tr){
	if(l>r)return {-INF,0};
	if(l==tl && r==tr)return t[v];
	int tm = (tl+tr)/2;
	return max(query(ch[0][v],l,min(r,tm),tl,tm),
	           query(ch[1][v],max(l,tm+1),r,tm+1,tr));
}
void reset(){
	for(int i=0;i<=ndcnt;i++){
		t[i] = {-INF,0};
		ch[0][i] = ch[1][i] = 0;
	}
	ndcnt = 0;
}
vector<array<int,4>>seg;
void fetch(int v,int l,int r,int tl,int tr){
	//cout<<l<<" "<<r<<" "<<tl<<" "<<tr<<'\n';
	if(l>r)return;
	if(l==tl && r==tr){
		seg.pb({v,l,r,0});
		return;
	}
	int tm = (tl+tr)/2;
	fetch(ch[0][v],l,min(r,tm),tl,tm);
	fetch(ch[1][v],max(l,tm+1),r,tm+1,tr);
}
int main()
{
	owo
	int n,k;
	cin>>n>>k;
	vector<pii>p(n),y(n);
	vector<int>id(n);
	for(int i=0;i<n;i++)cin>>p[i].fi>>p[i].se;
	sort(all(p));
	for(int i=0;i<n;i++){
		y[i].fi = p[i].se;
		y[i].se = i;
	}
	sort(all(y));
	map<int,int>r; //right border of fixed value of y
	//cout<<"sort\n";
	for(int i=0;i<n;i++){
		//cout<<p[i].fi<<" "<<p[i].se<<'\n';
		r[y[i].fi] = i;
		id[y[i].se] = i;
	}
	//for(int i=0;i<n;i++)cout<<id[i]<<" ";
	//cout<<'\n';
	int root = build(0,n-1);
	for(int i=0;i<n;i++){
		int oldsz = sz(seg);
		fetch(root,0,r[p[i].se],0,n-1);
		for(int j=oldsz;j<sz(seg);j++)seg[j][3] = i;
		root = upd(root,0,n-1,id[i],p[i].fi+p[i].se);
	}
	priority_queue<pair<ll,ll>,vector<pair<ll,ll>>,greater<pair<ll,ll>>>pq;
	int m = sz(seg);
	for(int i=0;i<m;i++){
		pii res = t[seg[i][0]];
		if(res.fi == -INF)continue;
		int id = seg[i][3];
		ll c = p[id].fi+p[id].se;
		c-=res.fi;
		pq.push({c,i});
	}
	for(int j=0;j<k;j++){
		if(pq.empty())break;
		glo.pb(pq.top().fi);
		int i = pq.top().se;
		pq.pop();
		
		pii res = t[seg[i][0]];
		seg[i][0] = upd(seg[i][0],seg[i][1],seg[i][2],res.se,-INF);
		
		res = t[seg[i][0]];
		if(res.fi == -INF)continue;
		int id = seg[i][3];
		ll c = p[id].fi+p[id].se;
		c-=res.fi;
		pq.push({c,i});
		
	}
	reset();
	root = build(0,n-1);
	seg.clear();
	while(!pq.empty())pq.pop();
    for(int i=0;i<n;i++){
		if(r[p[i].se] != n-1){
			int oldsz = sz(seg);
			fetch(root,r[p[i].se]+1,n-1,0,n-1);
			for(int j=oldsz;j<sz(seg);j++)seg[j][3] = i;
		}
		root = upd(root,0,n-1,id[i],p[i].fi-p[i].se);
	}
	m = sz(seg);
	//cout<<m<<'\n';
	for(int i=0;i<m;i++){
		pii res = t[seg[i][0]];
		if(res.fi == -INF)continue;
		int id = seg[i][3];
		ll c = p[id].fi-p[id].se;
		c-=res.fi;
		pq.push({c,i});
	}
	for(int j=0;j<k;j++){
		if(pq.empty())break;
		glo.pb(pq.top().fi);
		int i = pq.top().se;
		pq.pop();
		
		pii res = t[seg[i][0]];
		seg[i][0] = upd(seg[i][0],seg[i][1],seg[i][2],res.se,-INF);
		
		res = t[seg[i][0]];
		if(res.fi == -INF)continue;
		int id = seg[i][3];
		ll c = p[id].fi-p[id].se;
		c-=res.fi;
		pq.push({c,i});
		
	}
	sort(all(glo));
	//for(ll x:glo)cout<<x<<'\n';
	for(int i=0;i<k;i++)cout<<glo[i]<<'\n';
	//cout<<'\n';
	
	
}

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 7 / 7
• Subtask 4: 20 / 20
• Subtask 5: 27 / 27
• Subtask 6: 35 / 35